Pulley for high-speed transmission.



M. LEBLANC.

IULLEY FOR HIGH SPEED TRANSMISSION.

APPLICATION FILED DEC. 6, 1912.

1.21 8,67%. Patented Mar. 13, 1917.

STATES ENT rare MAURICE LEBLANC, OF VAL SUR SEINE, PAR CROISY, FRANCE,ASSIGNOR TO SOCIETE ANONYME POUR LEXPLOITATION PARIS, FRANCE.

DES rnoon'mts WESTINGHOUSE-LEBLANC, or

PULLEY FOR HIGH-SPEED TRANSMISSION.

Application filed December 6, 1912.

To all whom it may concern:

Be it known that I, MAURICE LEBLANo, of Val sur Seine, par Croisy, Seineet Oise, France, have invented new and useful Improvements in Pulleysfor High-Speed Transmission, of which the following is a specification.

The advance that hasoccurred in indus try by the employment of steamturbines has long since brought into prominence the question of thetransmission of motion between a shaft turning several thousand times aminute and a shaft rotating at less speed.

Up to the present one has generally been content to construct turbinesto turn as slowly as possible and to design apparatus to turn as quicklyas to enable it to be driven directly, that is to say to connecttogether two machines both of which work under difiicult or evenundesirable conditions.

This is not capable of a problematical solution and high speed gearingshave to be employed in cases where one cannot absolutely do otherwise.

It has been proposed to substitute for these gearings, which areexpensive and of a heavy nature, a transmission by pulleys and belts.

This invention relates to such a transmission, with very light beltscapable of a linear speed of 70 to 100 meters per second, which leads tothe employment, even for more rapid angular speeds of a turbine, ofpulleys having a sufficiently large diameter to enable a supple belt tocling to its surface.

The present invention has for its object a pulley that can acquirewithout danger peripheral speeds of 80.and 100 meters per second thatare essential for this kind of transmission.

A cast iron pulley cannot evidently run, without failure, at such aperipheral speed; steel pulleys are expensive and heavy, which is agreat drawback to high speeds.

The rim ought itself to be able to resist the centrifugal force. Now, itis known that with equal length and mass, filaments composed ofvegetable or animal fibers are more resisting than steel bands.

A hoop, formed for example, with glued ramie threads or filaments willresist centrifugal force better than a steel ring of Specification ofLetters Patent.

Patented Mar. 13, 1917.

Serial No. 735,256.

the same geometrical figure and turning at the same speed.

Moreover, the ramie hoop will be about seven times lighter than theother. The particular characteristic of a pulley according to thisinvention is in forming the felly or rim by a bobbin of animal orvegetable filaments impregnated with anagglutinant such as vulcanizedcaoutchoue, gelatin, or artificial cellulose as cellit, viscose, loreid,etc.

An embodiment of the invention is illustrated in the accompanyingdrawing wherein is shown a transverse sectional View of the pulley.

In the figure, is represented, by way of example, a section of a pulleywhich has a steel nave and arms I) supporting a band K of thin plate,such as is used for bicycles. The pulley being mounted on a shaft, thereis wrapped around the band K a long continuous filament of ramie,cotton, flax, hemp, silk, camel hair, or other suitable substance, inregular and successive layers which are successively impregnated with anagglutinant, each fresh layer being left to dry if the agglutinant isapplied in solution, e. g. gelatin, or artificial cellulose, or at theend the entire pulley is placed in a vulcanizing furnace if caoutchoucis used. This filar structure forming the rim of the pulley isdesignated by L.

The tension with which the filament is wound will be determined exactly,and will change from one layer to another so that it will always atleast be equal to that resulting from centrifugal force during rotation.Any form canbe given to the rim, cylindrical (fiat face) or arched(crown face), with one or more grooves, etc. It can be of any size andbe such as to constitute a drum.

Fly wheels can be similarly constructed, the mass of which will beparticularly small compared with the stored power.

The body of the pulley and the light band serving to support the bobbincan be formed -in any desired manner. They may be of paper or compressedpasteboard, protected or reinforced with vegetable or animal fibers.

In the direction transverse to the difl'erent spirally wound layers,circular bands 72 p may be disposed between consecutive spirally woundlayers, as shown, forming a cylinder around the pulley, which bands maybe formed of filaments or threads of vege- 5 table or animal fibersagglutinated together.

What is claimed is 1. A pulley having a rim said rim having a tensionmember comprising spirally wound layers of organic filamentary materials:3 adapted to sustain the centrifugal force acting upon the pulley and acircular band of threads parallel to the axis of the pulley between saidspirally wound layers.

2. A pulley havlnga rim said rim havreiae'za

